When film is exposed in a conventional camera it is normally advanced from left to right. A film magazine can be loaded on the left hand side and wound in the normal wind direction, i.e. the first or lowest numbered frame is exposed first and the film is returned back into the magazine, after all the pictures are taken, or it can be wound in the reverse wind direction, in which the film is first extracted out of the magazine and returned to the magazine as each picture is taken, i.e. the first frame on which a picture is taken is the first frame wound onto the magazine and corresponds to the highest numbered frame. The film magazine may also be loaded on the right hand side of a camera and either normal wind or reverse wind film transport techniques may be used. Cameras which utilize right hand load and a reverse wind technique include the increasingly popular single use cameras (SUC's) where it is more economical and reliable to put the magazine on the right side and thus eliminate the rewinding mechanism. A right hand load camera causes the scene on the film to be inverted when it is printed by an optical printer because, by convention, the printer receives the lowest numbered end of the film first and prints from the lowest frame number on the film to the highest frame number.
As the film is advanced into the print gate of the printer, the negative is first scanned for classification. However, the printer has no way to detect if the scene is an inverted or normal scene. The knowledge of the image orientation of a scene has application for conventional optical printing since this information is critical to the exposure determining algorithms in the printer software. Automatic digital imaging applications, such as the production of compact discs containing photographic images, and index prints on such discs, digitally printed automatic album pages, etc., also require that the images be correctly oriented before the final output image format is generated. At present, the scene inversion information is normally manually inputted to the printer setup values and remains fixed until the operator changes it. If this value is set to the normal scene orientation setting, then all film is treated in like manner, even if it is right hand load. Therefore, the best exposure will not be given to right hand load film. It is desirable to provide a means to detect and automatically tell the printer if a roll of film is a left or right (inverted) hand load film so that the required algorithms in the printer software can be activated, and the images can be printed right side up for conventional prints or digital and other multi image media.
Normally photo finishing operators sort customer films into batches of similar film for processing. It is not usually possible for the operator to identify the scene orientation of film from a reloadable camera. However, when the film is from a single use camera it is readily identified because the camera itself is opened by the photo finisher to retrieve the magazine and thus the right hand load film can be separated from other film. Once the film is identified as right hand load film by the photo finisher the printer can be signaled accordingly. This is a slow and therefore costly procedure when done by hand for multiple rolls of film.
U.S. Pat. No. 4,659,213 discloses a method and apparatus for detecting image information which has been recorded on the marginal portion of a film negative sheet outside of the film image. The marginal information, such as bar codes, may be used during photographic printing so as to discriminate the front surface from the back surface and/or to discriminate the top edge of the film from the bottom edge. If the negative film is mounted in an inverse direction, the printing exposure amount and correction may be determined.
SUC's use normal film which can be readily identified as right hand load and sorted manually. There is a need for a way in which normal film, exposed in either left or right hand load cameras, can be encoded as to orientation and processed in existing photo finishing equipment at high speed and therefore at low cost.
U.S. Pat. No. 4,800,406 discloses a method and apparatus for creating and checking correlation between negatives and prints in photographic laboratories by joining adjacent pairs of filmstrips with splicing tapes bearing machine-readable control numbers that are unrelated to orientation and reproducing each of said numbers onto the print medium at the printing station.
U.S. Pat. No. 5,248,887 discloses a method and apparatus for determining the orientation of film by providing the strip of exposed film with a timing track along one of the longitudinal margins thereof. The track includes a sequence of three segments. A sensor detects the position and width of the segments to determine the orientation of the film and thus distinguishes that the emulsion side is correctly oriented and whether the first or last exposure was inserted as the leading end. Using suitable printers an incorrectly oriented film can be detected and inverted electronically so that the image can be printed with the correct orientation.
While the foregoing patents '213 and '887 describe a way in which to detect orientation of a filmstrip by using specially coded filmstrip and apparatus designed to detect such codes they require special film and increase the complexity of film processing and therefore increase the cost of making prints.
In the present application, the term "imaging" is used as a blanket term for techniques used to convert an image on a film into a format for viewing, such as optical printing or digital scanning for printing, video displaying or projecting, the term "imaging parameters" is used as a blanket term for those variables which can be set for photofinishing equipment, in order to produce a viewable image, such as scene orientation, subject classification, exposure determination and color, density and contrast determinations.